1. Field of the Invention
The present invention relates to a liquid crystal display (LCD), and more particularly, to an LCD in which an electrostatic protecting circuit is arranged using a narrow signal line interval.
2. Discussion of the Related Art
Generally, an LCD includes a liquid crystal panel, a light source, and a driving circuit.
The liquid crystal panel includes upper and lower transparent substrates, and a liquid crystal layer in which a liquid crystal is injected between the upper and lower transparent substrates.
A common electrode, a black matrix layer, and a color filter layer are formed on the upper transparent substrate. A plurality of gate lines are arranged on the lower transparent substrate in one direction at constant intervals. A plurality of data lines are arranged at constant intervals in a vertical direction to the gate lines, so that an LCD array is formed in crossing points of the gate lines and the data lines. In the LCD array, a pixel region is formed in a space between the respective gate and data lines. A pixel electrode and a thin film transistor are arranged in each pixel region. A gate electrode is connected to the gate lines, a source electrode is connected to the data lines, and a pixel electrode is connected to a drain electrode, so that the thin film transistor is selectively turned on in accordance with a signal applied to the gate lines. Thus, a data signal of the data lines is applied to the pixel electrode. The respective gate and data lines are electrically connected to a driving circuit.
In the aforementioned LCD, since static electricity occurs during process steps or test, it is likely that devices of the LCD array are destroyed and damaged if the static electricity is applied to the gate lines or the data lines.
To protect the LCD array from the static electricity, the common electrode is formed between the driving circuit and the LCD array in a vertical direction to the gate and data lines, and an electrostatic protecting circuit is formed in either a crossing portion of the data lines and the common electrode or a crossing portion of the gate lines and the common electrode.
If the electrostatic protecting circuit is formed as above, equivalent potential to the common electrode is formed in the gate lines and the data lines by the electrostatic protecting circuit. Accordingly, even if the static electricity is applied to the gate lines or the data lines, it does not affect the devices of the LCD array.
A related art LCD provided with the aforementioned electrostatic protecting circuit will be described with reference to the accompanying drawings.
FIG. 1 is a schematic view of a related LCD provided with an electrostatic protecting circuit.
In the related art LCD, since a pixel size is greater than the electrostatic protecting circuit, the electrostatic protecting circuit is arranged in parallel.
As shown in FIG. 1, in a state that a common electrode 4 is arranged between a driving circuit 1 and an LCD array 2 in a vertical direction to data lines 3 or gate lines, an electrostatic protecting circuit 5 is arranged in one direction to correspond to portions, one to one, between the respective data lines 3 in crossing portions of the common electrode 4 and the data lines 3.
The respective data line 3 or the respective gate line is formed in a straight line between the driving circuit 1 and the LCD array 2.
However, the related art LCD provided with the electrostatic protecting circuit has several problems.
Since the electrostatic protecting circuit is arranged between the respective data lines in the crossing portion of the data line and the common electrode, it is difficult to arrange the electrostatic protecting circuit if the pixel size is smaller than the electrostatic protecting circuit.
In other words, since a space is narrow between the data lines in the LCD of high resolution, it is difficult to arrange the electrostatic protecting circuit therein. The LCD of high resolution cannot be obtained due to the electrostatic protecting circuit.